Why did 40% of the human population evolve to tolerate lactose?(1 point)

Question

Responses

Lactose tolerance allows people to enjoy a wide variety of food, including milk, butter, ice cream, and cheese.
Lactose tolerance allows people to enjoy a wide variety of food, including milk, butter, ice cream, and cheese.

People who have an intolerance experience physical pain, so a tolerance evolved to avoid that.
People who have an intolerance experience physical pain, so a tolerance evolved to avoid that.

Within cultures that rely on milk-producing animals, individuals who tolerated lactose had a survival advantage.
Within cultures that rely on milk-producing animals, individuals who tolerated lactose had a survival advantage.

Babies rely on milk to survive, so they need to be able to tolerate lactose.

What is the difference between genetic drift and natural selection?(1 point)
Responses

Genetic drift is the change in a population’s genes over time; natural selection is the evolution of a population over time.
Genetic drift is the change in a population’s genes over time; natural selection is the evolution of a population over time.

Genetic drift is the random increase or decrease of certain genes in a population; natural selection is not random.
Genetic drift is the random increase or decrease of certain genes in a population; natural selection is not random.

Genetic drift is the frequency of genes in a population; natural selection is the frequency of adaptations in a population.
Genetic drift is the frequency of genes in a population; natural selection is the frequency of adaptations in a population.

Genetic drift is the selection of random traits in a population; natural selection is the selection of specific traits.
Genetic drift is the selection of random traits in a population; natural selection is the selection of specific traits.

What is an interferon?(1 point)
Responses

An interferon activates the body’s immune system response to a virus.
An interferon activates the body’s immune system response to a virus.

An interferon reduces the efficacy of antibiotics on bacteria.
An interferon reduces the efficacy of antibiotics on bacteria.

An interferon is used by a virus to stop the body from detecting it.
An interferon is used by a virus to stop the body from detecting it.

An interferon disrupts DNA replication.

Why is there such a wide variety of immune system responses between hosts when they are infected with the same virus?(1 point)
Responses

People that have already been infected are asymptomatic.
People that have already been infected are asymptomatic.

Some viruses are resistant to antibiotics, so they cause a stronger immune system response.
Some viruses are resistant to antibiotics, so they cause a stronger immune system response.

Each person’s immune system employs different tactics to get rid of the virus.
Each person’s immune system employs different tactics to get rid of the virus.

Slight variations due to mutations in the virus trigger different responses in people.

s the following statement true? “Antigenic drift and other mutations to the DNA of viruses are always beneficial for the virus.”(1 point)
Responses

Yes, because mutated viruses have less mRNA so they can copy and replicate faster.
Yes, because mutated viruses have less mRNA so they can copy and replicate faster.

No, because mutated viruses may be less likely to replicate.
No, because mutated viruses may be less likely to replicate.

Yes, because mutated viruses are able to infect more hosts.
Yes, because mutated viruses are able to infect more hosts.

No, because different mutations cause a variety of immune responses.

Answer 1

Here are the best responses for each question:

1. Why did 40% of the human population evolve to tolerate lactose?

   • Response: Within cultures that rely on milk-producing animals, individuals who tolerated lactose had a survival advantage.

2. What is the difference between genetic drift and natural selection?

   • Response: Genetic drift is the random increase or decrease of certain genes in a population; natural selection is not random.

3. What is an interferon?

   • Response: An interferon activates the body’s immune system response to a virus.

4. Why is there such a wide variety of immune system responses between hosts when they are infected with the same virus?

   • Response: Each person’s immune system employs different tactics to get rid of the virus.

5. Is the following statement true? “Antigenic drift and other mutations to the DNA of viruses are always beneficial for the virus.”

   • Response: No, because mutated viruses may be less likely to replicate.